gdbrunner: Fix find_binary's named argument.

Rename it from `user` to `run_as_cmd` to match the use of this method
in handle_switches in scripts/gdbclient.py.

Test: Run scripts/gdbclient.py -p <PID> on suspended process having pid <PID>
Change-Id: I9820858b1f43d5cb25a9a59e9df618ed4e47f3f0
1 file changed